timer: add setup_deferrable_timer macro

Add the trivial missing macro to setup a deferrable timer.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/timer.h b/include/linux/timer.h
index 61aa61d..20ac746 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -145,6 +145,8 @@
 
 #define setup_timer(timer, fn, data)					\
 	__setup_timer((timer), (fn), (data), 0)
+#define setup_deferrable_timer(timer, fn, data)				\
+	__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE)
 #define setup_timer_on_stack(timer, fn, data)				\
 	__setup_timer_on_stack((timer), (fn), (data), 0)
 #define setup_deferrable_timer_on_stack(timer, fn, data)		\